Control of Coercivities in (Ga,Mn)As Thin Films by Small Concentrations of MnAs Nanoclusters

TL;DR

This paper shows that introducing small amounts of MnAs nanoclusters into (Ga,Mn)As thin films significantly increases coercivity without harming the Curie temperature or saturation magnetization, advancing ferromagnetic semiconductor device potential.

Contribution

It presents a novel method to control coercivity in (Ga,Mn)As films by embedding MnAs nanoclusters, maintaining high Curie temperatures.

Findings

Coercivity increased by up to 100 times.

MnAs nanoclusters average size ~7nm.

High Curie temperature preserved.

Abstract

We demonstrate that low concentrations of a secondary magnetic phase in (Ga,Mn)As thin films can enhance the coercivity by factors up to ~100 without significantly degrading the Curie temperature or saturation magnetisation. Magnetic measurements indicate that the secondary phase consists of MnAs nanoclusters, of average size ~7nm. This approach to controlling the coercivity while maintaining high Curie temperature, may be important for realizing ferromagnetic semiconductor based devices.